1. Field of the Invention
The present invention relates to a system for controlling the winding of a ribbon on a receiver reel, the ribbon being designed for the thermal transfer of coloring agents that are arranged sequentially on the ribbon.
2. Description of the Prior Art
There is the known technology of thermal transfer in which the coloring agent is deposited and fixed to the surface to be printed by means of the resistors that form a thermal printer head heating a ribbon, coated with coloring agents, by means of a modulated electrical current.
There is also the known technology of thermal transfer whereby there are sequentially deposited primary coloring agents, namely yellow, magenta, cyan that can be used for the obtaining, by the combination of different wavelengths called subtractive wavelengths, of a range of several millions of colors and shades.
To obtain high-definition printing quality, especially in work for the graphic customizing of memory cards, it is imperative to achieve perfect synchronization of the speed at which the ribbon runs under the printing head with the speed of horizontal translation of the card to be printed under said head.
The ribbon is presented wound on a storage reel the shaft of which rotates freely. Another reel, called a receiver reel, is used to wind the ribbon after use and is provided with a driving motor means. For a constant speed of linear shift beneath the thermal printing head, the winding speed, expressed in turns of the receiver reel, varies at each turn since the diameter of the circumference of the winding drum increases by the thickness of a new wound layer.